QPR 9: Ninth Quarterly Progress Report for NIH Project N01-DC-2-1002 (April 1, 2004 through June 30, 2004) -- Speech Processors for Auditory Prostheses
The main objective of this project is to design, develop, and evaluate speech processors for implantable auditory prostheses. Ideally, such processors will represent the information content of speech in a way that can be perceived and utilized by implant patients. An additional objective is to record responses of the auditory nerve to a variety of electrical stimuli in studies with patients. Results from such recordings can provide important information on the physiological function of the nerve, on an electrode-by-electrode basis, and can be used to evaluate the ability of speech processing strategies to produce desired spatial or temporal patterns of neural activity. Work and activities in this quarter included: (1) Studies April 19-23 with subject NP-8, implanted with an experimental version of the Nucleus device that provides percutaneous access to a Contour electrode array. The studies included consonant identification tests with a variety of experimental processors, and melody identification tests with a selected subset of processors. (2) Studies May 3-7 with German Med-El C40 /TEMPO subject ME-20, a routine user of combined electrical and contralateral aided acoustic stimulation (EAS). This subject has considerable residual acoustic hearing sensitivity up to at least 1 kHz in both ears. In addition to speech reception comparisons with a variety of combined stimulation designs, studies during this visit included pitch ranking, pitch scaling, pitch matching, and pitch DL measurements relating electrically and acoustically stimulated pitch percepts in the same ear. (3) Presentation by Wilson at the Eighth International Cochlear Implant Conference, Indianapolis, IN, May 10-13. (4) Presentation by Wilson at the Med-El Satellite Symposium, in conjunction with the Eighth International Cochlear Implant Conference, Indianapolis, IN, May 10-13. (5) Further studies May 24-25 with Nucleus percutaneous subject NP-8. Studies included tests of word identification in CUNY sentences with many of the processors investigated during that subject’s preceding visit. (6) Studies June 7-8 with Nucleus percutaneous subject NP-6, including consonant identification tests with a variety of CIS processor configurations.